In the age of modern communication and information technology, optical data transmission by way of glass fiber cables plays a critical role. The design of reliable optical networks is dependent on the capability to cut glass fiber cables, which are also referred to in the following text as optical fibers or optical waveguides, such that a defined end surface, in particular an end surface which is as planar as possible, is produced at the end of the cut glass fiber cables. Planar end surfaces are required, for example, for splicing, that is to say thermal connection of two glass fiber cables to form a new, longer glass fiber cable, when the spliced joint is intended to result in the optical losses being as low as possible. Planar end surfaces are likewise required for low-loss optical coupling between an optical fiber and an optical connector or an optical coupling.
Optical fibers are generally cut by positioning the glass fiber at the point to be cut parallel over an anvil in an apparatus for cutting optical fibers, and by scoring it at right angles to the glass fiber. This can be done by using a scoring apparatus. When the optical fiber is subsequently bent, it preferably breaks at the scoring point. High-quality cutting apparatuses for glass fibers are in consequence distinguished in that the broken surface, which runs at right angles to the glass fiber axis, is as planar as possible, and in that the broken surface quality is subject to as few fluctuations as possible over a large number of cutting processes.
DE 33 17 304 A1 discloses an apparatus for cutting optical waveguides, which allows a high broken surface quality to be achieved, that is to say the broken surfaces of cut glass fibers are essentially free of disturbing notches, scratches and other uneven features. The high broken surface quality is achieved by providing a slot in an anvil, thus producing a symmetrical stress distribution in the cross section of the glass fiber at the scoring point. In this case, the width of the slot is governed by the diameter of the fiber to be cut.
DE 33 22 127 A1 discloses a method and an apparatus for cutting optical waveguides, in which the optical waveguide to be cut is held firmly with the aid of two clamping devices, is prestressed over an anvil in the axial direction with the aid of a tensioning device, and is scored transversely axially at the cutting point on the anvil with the aid of a scoring device. Manual intervention during the operation of the cutting apparatus is largely precluded, in order to ensure that the quality of the broken surfaces that are produced during the cutting process is uniformly high. This is achieved by way of a common operating element, by which the scoring device, the clamping devices and the tensioning device are each moved against a spring force to a position such that the clamping devices, tensioning device and the scoring device are operated autonomously and successively after the insertion of the optical waveguide to be cut and when the load on the operating element is removed.
Furthermore, WO 99/47954 discloses a cutting apparatus for optical fibers, which has a control device, which can be operated manually, as well as functional elements for successive clamping, scoring and breaking of the fibers.
All the functional elements are operated by way of the control device. Transmission elements and spring elements are provided between the, control device and the functional elements, and allow the functional elements to be moved in a defined sequence as a function of the forward and return movement of the control device.
EP 0 528 636 A1 discloses an apparatus both for cutting and for splicing optical waveguides, in which, after a cutting process, the optical waveguides to be spliced can be transferred by means of a transfer apparatus, which can pivot, from the cutting apparatus in the correct orientation to the splicing apparatus.
U.S. Pat. No. 4,463,886, DE 29 19 121 and U.S. Pat. No. 6,122,936 each disclose cutting apparatuses for optical waveguides, in which the optical waveguides are slightly curved before the scoring process. As a result of the mechanical stress which is caused in the optical waveguide by the bending process, the optical waveguide is broken by the scoring process, resulting in a largely planar optical waveguide end surface.
The known cutting apparatuses for optical fibers have the disadvantage that the fiber is inserted into the cutting apparatus manually, so that there is a risk of the cylindrical outer surface of the cylindrical fiber being mechanically damaged, particularly in the vicinity of the cutting point. This thus considerably reduces the tensile strength of the spliced glass fibers.